(1) Field of the Invention
This invention is directed to the field of measurement and testing, and more particularly, to a contamination capacitance probe system.
(2) Description of the Prior Art
In many applications different systems and subsystems employ or are exposed to two or more fluids or materials where their mutual separation is essential to achieving the intended control or other action, and where their co-mingling effects an undesirable contamination. Examples are water or other contaminate in the fuel of a fuel burning system; metal, water or other contaminate in the motor oil of an internal combustion engine, and seawater in an hydraulic ballast and buoyancy compensation unit of an unmanned undersea vehicle, among others.
Whenever the fluids or materials that should be kept separated are caused to mingle, due to a failure of some component, system, subsystem or other cause, the ability of the component, system or subsystem or other device to perform its function or intended design mission becomes compromised. In the hydraulic ballast and buoyancy compensation unit of an unmanned undersea vehicle, for example, the failure of a rubber bladder that is controllably expanded and contracted by pumping hydraulic oil thereto to displace different quantities of seawater into and out of the ballast tank of the undersea vehicle could prevent the undersea vehicle from trimming to a positive buoyancy state and therewith prevent its surface recovery.
Resistance-type and capacitance-type sensors are known that measure changes in level of a fluid or material in which they are immersed or with which the are brought into contact. The utility of these heretofore known sensors, however, is limited to sensing level changes of a single fluid or material but are generally incapable of responding to and providing a signal representative of two or more fluids or materials having been mixed or mingled. In the case of seawater and oil, for example, the presence of the oil, that acts to coat such prior art level sensors both of the resistance-type and capacitance-type, effectively prevents their ability to respond to the presence of the seawater and oil after they have been mixed or mingled.